Hair repigmentation (HR) is a non-described effect secondary to anti-programmed cell death 1 (anti-PD-1: nivolumab, pembrolizumab) and anti-programmed cell death ligand 1 (anti-PD-L1: atezolizumab) therapy for treatment of lung cancer (LC), in opposition to the vitiligo reactions that develop during melanoma treatment.
In this interesting article, Rivera et al described a case series of 14 patients (13 men and 1 woman; mean age, 64.9 years) with HR after anti-PD-1/anti-PD-L1 treatment for LC. This HR consisted of a diffuse darkening of the hair in 13 of 14 patients, or in black patches between white hairs in 1. Since 13 out of 14 patients presented a good clinical response to the treatment (with at least stable disease), HR might be a marker for good response in patients receiving anti-PD1/anti-PD-L1 therapy for LC.
The mechanisms of drug-induced HR are not clear, although some hypotheses have been proposed. Some authors propose that different drugs can inhibit proinflammatory cytokines (e.G. tumor necrosis factor-α, tumor necrosis factor-β, in- terleukin 1 and interleukin 6) that act as negative regulators of melanogenesis, explaining this repigmentation. Other authors propose an almost opposed hypothesis: melanocytes in hair follicles might be activated through inflammatory mediators, such as cytokines and reactive oxygen species, explaining the localized HR after an induced folliculitis.

Minoxidil can stimulate hair growth, and its topical form is used in the treatment of female pattern hair loss and male pattern baldness. Some isolated reports described the usefulness of oral minoxidil in androgenetic alopecia. The objective of this study was to evaluate the effectiveness of oral minoxidil in the treatment of chronic telogen effluvium (CTE).
In the present study, Dr Perera and Dr Sinclair included 36 women (mean age of 47 years, range 20-83) with CTE treated with oral minoxidil (range 0.25-2.5 mg) daily for 6 months. There was a reduction in mean hair shedding scores from baseline to 6 months of 1.7 (p<0.001) and baseline to 12 months of 2.58 (p<0.001). Mean change in blood pressure was minus 0.5 mmHg systolic and plus 2.1 mmHg diastolic. Thirteen women (36%) developed facial hypertrichosis. All 36 women completed 12 months of treatment.
Based on these results, oral minoxidil appears to reduce hair shedding in CTE. Future comparative studies are recommended to further assess this response.

The objective of this study by Dr. Saceda-Corralo et al was to create and validate a new severity scale for FFA (”Frontal Fibrosing Alopecia Severity Score” FFASS) that include both signs and symptoms of the disease. The parameters selected included clinical characteristics with a good correlation with the disease severity: extent of alopecia, eyebrow loss, inflammatory signs (perifollicular erythema and hyperkeratosis) and symptoms (pruritus and pain). The resulting severity score ranges from 0 (less severe) to 25 (more severe).
Criterion validity was assessed by the Investigator’s Global Assessment scale, and construct validity was evaluated by the convergence of other measures of severity (the Patient’s Global Assessment scale), the rest of the clinical features, the Lichen Planopilaris Activity Index, and quality of life measures (Dermatology Life Quality Index and Hospital Anxiety Depression Scale). Intraobserver and interobserver reliability were determined.
In total, 103 female patients were included. The FFASS showed significant correlation to the Patient’s Global Assessment scale, occipital involvement, and the Lichen Planopilaris Activity Index. Intraobserver reliability was completed for 31 subjects and showed good correlation (intraclass correlation coefficient, 0.86; 95% confidence interval, 0.7-0.95; P < .001). Interobserver reliability showed excellent correlation (intraclass correlation coefficient, 0.97; 95% confidence interval, 0.95-0.99; P < .001).
In conclusion, the FFASS is a statistically validated scale and a reliable measure of FFA severity, and it can be used in clinical practice and future research studies as an assessment tool.

The objective of this interesting study by Rakowska et al was to assess the efficacy of systemic retinoids in treating frontal fibrosing alopecia (FFA). The study was based on a retrospective analysis of 54 female patients with FFA treated with oral isotretinoin at the daily dose of 20 mg (29/54), acitretin at the daily dose of 20 mg (11/54) or with oral finasteride 5 mg/day (14/54).
No further progression of disease after 12 months of treatment was observed in 76% (23/29) of patients treated with isotretinoin, 73% (8/11) of patients treated with acitretin, and 43% (6/14) of patients treated with finasteride. No further progression of disease following the discontinuation of systemic retinoids was observed in 72% (21/29) of patients treated with isotretinoin, 73% (8/11) of patients treated with acitretin, and 43% (6/14) of patients treated with finasteride. The potential mechanism of action might be the normalization of hair follicular keratinocyte antigen expression or the suppression of inflammatory cellular infiltration, although it requires further research.
In conclusion, systemic retinoids may be beneficial for the stabilization of frontal hairline in patients with FFA, a statement to be confirmed in future studies.

Androgenetic alopecia (AGA) is a multifactorial disorder caused by synergy of gene, endocrine, and aging. Current studies on AGA mainly focused on the whole hair follicle or the acknowledged target dermal papillae (DP). However, hair follicle stem cells (HFSCs) in the bulge area also exert a great influence on AGA. Since the exact role of different parts of the hair follicle in AGA etiology remains unclear, Miao et al performed a transcriptome profiling in the bulge and DP of AGA patients and controls in balding and non-blading areas. In their profiling results, compared with control groups, genes regulating inflammation, stress and fibrosis were massively over-expressed in all AGA groups. Among the inflammation regulators, the bulge-containing parts had more elevated inflammation-related genes than the DP-containing parts. This study may provide us with novel insights of AGA pathogenesis, including pathologic framework of “inflammation–stress–fibrosis” and disturbed HFSCs maintenance.

In this study, Pirastu et al present the results of a genome-wide association study including more than 70,000 men, identifying 71 independently replicated loci, of which 30 are novel. These loci explain 38% of the risk.
The authors identified and replicated numerous new loci predisposing to male pattern baldness (MPB) which, together with the previously identified ones, can explain a large proportion of the estimated heritability. Interestingly, they showed that for many of them, multiple distinct Single Nucleotide Polymorphisms (SNPs) participate in determining MBP risk. They observed an h2-SNP of 94%, which suggests that MBP is more a polygenic trait than a complex one, with very little environmental component. It was also shown that MBP loci contain genes attributable to specific pathways, some of which predispose to other traits such as longevity and cancer.